Train-control receiving apparatus



` Aug. 31, 1926.

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muren stares -e 'i 41,597,810 vPartnr OFFICE.

SAMUEL IJI. .T iUGlr, OF ITTSB'URGH, PENNSYLVANIA, ASSIGN-OR T0 THEUNION SWITCH & SIGNAL COMPANY, 0F S'WISSVALE, PENNSYLVANIA, ACORPORATION O1? PENNSYLVANIA.

TRAIN-CONTROL RECEIVING APPARATUS. 4

Application filed July 6, 1925. Serial No. 41,559.

My invention relates to receiving apparatus, and particularly toapparatus suitable for use inV connection with train control systemswherein train carried mechanism is controlled atleast in part by analternating current which flows through the track rails. p p

One feature of my invention is the provision of a receiver which wouldsupply energy to the train carried mechanism in accordance withV thetrain controlling current in the trackway, but which will not supplyenergy to such apparatus in accordance with alternating currents flowingin adjacent conductors such as transmission lines or train propulsionmotor windings.

I will describe one form of receiving apparatus embodying my invention7and will then point out the novel features thereof in claims.

The accompanying drawing is a view7 partly diagrammatic and partly inperspective, illustrating one form of receiving` apparatus embodying myinvention.

Referring to this drawing, the reference characters 1 and 1n designatethe track rails of a stretch of railway track. Means are provided for attimes supplying a train con trolling current to these track rails. Inthe form here shown this train controlling current flows through the tworails in parallel. Two impedances designated by the refer.- encecharacters 2 and 2a are connected across the track rails at spacedpoints in the trackway7 and the train controlling current is supplied tothe mid-points of these i1npedances. The immediate source of the traincontrolling current is an alternator A, one terminal of which isconnected directly with impedance 27 and the other terminal of which isconnected with the impedance 2 through a circuit controller 3. Thiscircuit controller may be operated by any suitable means forming no partof my present invention, and omitted from the drawing for the sake ofsimplicity. In actual practice the circuit controller 3 will usually becontrolled 4in accordance with traflic conditions in advance.

A train, indicated diagrammatically at V, is provided with receivingapparatus comprising a magnetizable core 10 located in inductiverelation with the track rails. This core is provided with two downwardlyprojecting feet 102L located on opposite sides of the track rail 1. Twosimilar feet 10b depend from the core 110 on opposite sides of the trackrail 1a. The core 10 is provided with a windinglil intermediately thetwo feet 10, and asimilarwindingl is placed on core 10 intermediate thetwo feet 10b. The train controlling current `iowing'inV each rail 1 and1L creates a magnetic flux which surrounds the rails. A portion of theflux around rail 1 followsthe path 11 through feet 10a and core A10andso links onewind'- ing 14. A portion of ,the flux around rail 1a followsthe path 12 through feet 10b and core 10 and so links the other winding15. A portion of the flux which surrounds both rails passes through core10 along the path 13 and so links both windings 14: and 15. The windings14 and 15 are so connected in series that the voltages induced in thesewindings by the fluxes due to the train controlling current flowingthrough the rails 1 and 1a in multiple are additive. The terminals ofthe windings 111 and 15 are connected with a relay R which may be usedto control governing mechanism (not shown in the drawing) in anysuitable manner.

Under some conditions of operation, foreign fluxes may be present in thevicinity of the core 10. For example, a transmission line 7 extendingalong the trackway may cause a flux in the path 9. Similarly a motor Msuch as a propulsion motor on the train V may cause a flux in the path6. In the absence of any preventative means these fluxes may passthrough the core 10 andy create voltages in the windings 111 and 15 andmay therefore cause improper operation of the relay R. This isundesirable, and to prevent its occurrence I provide a shield Sisurrounding the core 10. This shield is constructed ofelectro-conducting material such as copper or aluminum. In the form hereshown this shield comprises a box having a top 16, two ends 17, and twosides 18. The bottom of this box is open. It is manifest that the shieldS has no effect upon the fluxes due to train controlling current in thetrack rails because these fluxes pass through the open bottom of theshield S.

Foreign fluxes from the transmission line 7 or from the motor M musthowever pass through the shield S. These fluxes create eddy currents inthe walls of the shield, which eddy currents react to oppose the passageof suoli foreign fluxes through the shield. As a result the amount ofsuch foreign fluxes which pass through core 10 is greatly reduced andthe effect of such` fluxes upon windings 14 and 15 is substantiallynegligible; f Y

I have herein illustrated my invention as applied to receiving apparatusfor use` in' connection With a train controlling current which flowsthrough the tivo rails in paral lel, but this particular method ofsupplying current to the'rails is not essential to my invention. f

It should be particularly pointed out that the shield S'prevents thepassage of iluxes through core lO except from a limited region, that is,from the'tracl rails,` and consequently the` shield will prevent thepaslsage of foreign fluxes through this core no matter What may be thesource of such fluxes.

`Although I" have herein shown and de- Y scribed only onek form ofreceiving apparatus embodying my invention, it is understood thatvarious changes and modifications may be made therein Within the scopeof the appended 'claims Without departing from the spirit and scope ofmy invention. Having thus described my invention, What Iclaim'isl. Atrain carried receiver comprising a magnetizable core located ininductive relation with a track rail, a Winding on said core, and meansassociated with said core for permitting the passage of magnetic fluxthrough said core from ak predetermined region only.

2. A train carried receivercomprising a magnetizable core in inductiverelation with both track rails, a Winding on said core, and a shield ofelectro-conducting material surrounding said core but having an openingbetween said core and theV track rails.

In testimony whereof I ailix my signature.

SAMUEL M. LUCAS.

